Grid responsive control device

Abstract

A load control device which is responsive to a physical variable representing the balance between load and generation on an electricity grid. The control device varies the energy consumption of the load based on the current value of the physical variable of the grid relative to a central value of that physical variable, which is derived from past readings of the physical variable of the grid. The grid responsive control device also takes into account the time since the load last varied its energy consumption in determining whether or not the grid variable load control should be provided.

1 - 26 . (canceled) 
     
     
         27 : A control device for controlling an energy consumption of a load on an electricity grid, said control device comprising:
 means for sensing over a period of time values of a physical variable of the grid, said physical variable varying in dependence on a relationship between electricity generation and load on the grid;   means for determining a historically based value of the physical variable of the grid from past readings of said values of the physical variable of the grid; and   means for increasing or decreasing the energy consumption of said load, said varying dependent upon a current physical variable of said grid, relative to said historically based value.   
     
     
         28 : The control device of  claim 27 , comprising:
 means for increasing or decreasing the energy consumption of said load when a current value of said sensed physical variable of the grid reaches a trigger value; and   means for determining said trigger value, said determining of said trigger value dependent upon said historically based value, and wherein a) said means for determining said trigger value comprises means for randomly providing said trigger value between a determined upper or lower value of the physical variable of the grid and said historically based value, and/or wherein b) said control device comprises means for sensing a value of a physical variable of the load, said physical variable representative of the energy stored by the load; said determining of the trigger value further dependent upon said sensed physical variable of the load.   
     
     
         29 : A control device for controlling the energy consumption of a load on an electricity grid, said control device comprising:
 means for sensing a value of a physical variable of the grid, said physical variable varying in dependence on a relationship between electricity generation and load on the grid;   means for sensing a value of a physical variable of the load, said physical variable of the load representative of the energy stored by the load;   means for varying the energy consumption of said load when a value of said physical variable of the grid reaches a trigger value; and   means for determining the trigger value, said determining of the trigger value dependent upon said sensed physical variable of the load and further based upon a random value.   
     
     
         30 : The control device of  claim 29 , wherein said means for varying comprises means for comparing said trigger value with the current sensed physical variable of the grid. 
     
     
         31 : The control device of  claim 29 , wherein the means for varying the energy consumption of the load is configured to vary the energy consumption of the load so as to maintain the sensed physical variable of the load within central limits and is further configured to vary the energy consumption when said value of the physical variable of the grid reaches the trigger value. 
     
     
         32 : The control device of  claim 31 , said means for determining the trigger value configured to determine the trigger value in dependence on the value of the sensed physical variable of the load relative to its minimum or maximum values. 
     
     
         33 : The control device of  claim 31 , said means for determining said trigger value comprising means for defining a trigger value profile varying with said physical variable of the load, said profile such that the more recently the energy consumption of the load has varied the further the trigger value is from a historically based value from past readings of the physical variable of the grid. 
     
     
         34 : The control device of  claim 29 , said means for determining said trigger value comprising means for defining a trigger value profile varying with said physical variable of the load, said profile being influenced by a random value. 
     
     
         35 : The control device of  claim 29 , wherein said sensed physical variable of the grid is a sensed frequency of the grid. 
     
     
         36 : The control device of  claim 29 , said means for varying configured to vary said energy consumption by switching the energy consumption between a first state of increasing the energy stored by the load and a second state of decreasing the energy stored by the load. 
     
     
         37 : A control device for controlling an energy consumption of a load on an electricity grid, said control device comprising:
 means for determining a random delay;   means for delaying the starting of energy consumption of said load by a randomly generated amount of time after power is initially provided to the control device.   
     
     
         38 : A control device for controlling an energy consumption of a load on an electricity grid to maintain a physical variable of the load within upper and lower limits, said control device comprising:
 means for sensing the physical variable of the load;   means for providing the upper and lower limits of the sensed physical variable of the load; and   means for increasing the upper and/or lower limit of the sensed physical variable at a rate less than a maximum energy consumption of the load after power is initially provided to the control device.   
     
     
         39 : A method of controlling an energy consumption of a load on an electricity grid, said control device comprising:
 sensing over a period of time values of a physical variable of the grid, said physical variable varying in dependence on an relationship between electricity generation and load on the grid;   determining a historically based value of the physical variable of the grid from past readings of said values of the physical variable of the grid; and   increasing or decreasing the energy consumption of said load, said varying dependent upon a current physical variable of the grid relative to said historically based value.   
     
     
         40 : The method of  claim 39 , comprising:
 varying the energy consumption of said load when a current value of said sensed physical variable of the grid reaches a trigger value; and   determining said trigger value, said determining of said trigger value dependent upon said central value.   
     
     
         41 : The method of  claim 40 , said determining said trigger value comprising a function for randomly providing said trigger value between a determined upper or lower value of the physical variable of the grid and said central value. 
     
     
         42 : The method of  claim 40 , comprising sensing a value of a physical variable of the load, said physical variable representative of the energy stored by the load; said determining of the trigger value further dependent upon said sensed physical variable of the load. 
     
     
         43 : A method of controlling the energy consumption of a load on an electricity grid, said method comprising:
 sensing a value of a physical variable of the grid, said physical variable varying in dependence on a relationship between electricity generation and load on the grid;   sensing a value of a physical variable of the load, said physical variable of the load representative of the energy stored by the load;   varying the energy consumption of said load when a value of said physical variable of the grid reaches a trigger value; and   determining the trigger value, said determining of the trigger value dependent upon said sensed physical variable of the load, and further based upon a random value.   
     
     
         44 : The method of  claim 43 , wherein said varying comprises comparing said trigger value with the current sensed physical variable of the grid. 
     
     
         45 : The method of  claim 43 , wherein the varying the energy consumption of the load comprises varying the energy consumption of the load so as to maintain the sensed physical variable of the load within control limits and further varying the energy consumption when said value of the physical variable of the grid reaches the trigger value. 
     
     
         46 : The method of  claim 43 , said determining the trigger value comprising determining the trigger value in dependence on value of the sensed physical variable of the load relative to its minimum or maximum values. 
     
     
         47 : The control device of  claim 45 , said determining said trigger value comprising defining a trigger value profile varying with said physical variable of the load, said profile such that the more recently the energy consumption of the load has varied the further the trigger value is from a historically based value determined from past readings of the physical variable of the grid. 
     
     
         48 : The method of  claim 47 , wherein said sensed physical variable of the grid is a sensed frequency of the grid. 
     
     
         49 : The method of  claim 48 , said varying comprising varying said energy consumption by switching the energy consumption between a first state of increasing the energy stored by the load and a second state of decreasing the energy stored by the load. 
     
     
         50 : A method of controlling an energy consumption of a load on an electricity grid, said method comprising:
 providing a control device, said control device determining a random amount of time;   delaying the starting of energy consumption of said load by a randomly generated amount of time after power is initially provided to the load.   
     
     
         51 : A method of controlling an energy consumption of a load on an electricity grid to maintain a physical variable of the load within upper and lower limits, said method comprising:
 sensing the physical variable of the load;   providing the upper and lower limits of the sensed physical variable of the load; and   increasing the upper and/or lower limit of the sensed physical variable at a rate less than a maximum energy consumption of the load after power is initially provided to the control device.